This invention relates to a speech recognition system, and more particularly, to a technology for providing, in the latest state, a user with recognition error patterns of a speech recognition system used in a navigation device.
A speech recognition system used in a car navigation device has an advantage of enabling operations on the device without constraining hands and eyes. Especially, car navigation devices offering a function of receiving a point of interest (POI) name uttered by a user as a speech input to thereby set a destination are in the market.
However, when a large number of words are registered in a dictionary of speech recognition held by the speech recognition system, sets of words causing recognition errors tend to occur, resulting in a lower possibility of recognition of a destination from an utterance of a user. To address this problem, JP 08-171396 A discloses a method in which tendencies of recognition errors among phonemes are obtained in advance, and, based on the tendencies, a result of performing error correction on an originally obtained recognition result based on the tendencies of recognition errors is added to a speech recognition result. Moreover, a method of, using tendencies of recognition errors, adding words other than words registered in a dictionary of speech recognition to a speech recognition result, is disclosed (see T. Fukada and Y. Sagisaka, “Automatic generation of a pronunciation dictionary based on a pronunciation network”, Proc. Eurospeech 1997, pp. 2471-2472, for example).
Further, JP 2006-317643 A discloses a technology of updating a map with a decreased data traffic by sending difference data of map data for a specific area from a navigation server (hereinafter, referred to as server) to a navigation terminal (hereinafter, referred to as terminal) via a network.
Still further, Shikano, et al., “Speech recognition system”, Ohmsha, 2001, describes a method of speech recognition.